Interview
with Neil Love, MD Breast Cancer Update for Medical Oncologists,
Program 6 2000
Play
Audio Below:
Dr.
Peto: What’s really solid is the benefit you get from the treatment
of women with ER+ disease, and that’s because there were a
lot more women with ER+ disease in these trials. So, both in terms
of what it does for contralateral and in terms of what it does for
the prevention of the original primary coming back and getting you,
the results for women with ER+ disease are absolutely definite.
For ER poor disease, women with ER-negative disease, the last time
around, it seemed as though you were getting about as much prevention
as in ER+, but it was barely statistically significant, the confidence
level went right the way down to zero. Now it seems that you’re
not getting very much. But, again, the confidence interval is really
very wide and pretty well includes the idea that you’re getting
as much benefit in ER-negative as ER-positive. People have been
making much too much of these small numbers, both last time around
and this time around.
The
overall conclusion in women with ER-negative disease is that there
is little or no net benefit. It’s still a research question
as to whether we should say little or no. But there’s not much
effect of tamoxifen in terms of 10-year outcome in women with ER-negative
disease. That was true last time, and it’s still true this
time, whereas, there’s a very substantial effect in women with
ER-positive disease, a very substantial benefit. You can’t
find any category of women, with ER-positive disease, where you
don’t have evidence of benefit.
Dr.
Love: One of the things that I’ve learned from you over the
years is, when you don’t see an effect, it might be because
there is no effect, but it also might be because there’s not
enough evidence. Now, my question to you is, in this specific question
of: does tamoxifen decrease the incidence of second breast cancers
in a women whose first breast cancer is ER-negative? At this point,
we don’t have evidence that that’s the case.
Dr.
Peto: The data are compatible with there being no such effect, but
they’re also compatible with there being quite a substantial
preventive effect there. They’re really not reliably informative
about this. The reliable information as to what tamoxifen does is
in women with ER-positive disease, there the benefits are clear.
I agree, theoretically, it would be very odd if it didn’t prevent
contralateral in women with ER-negative disease. The data suggests
some slight protective effect, but very little. But they’re
compatible with there being quite a substantial protective effect
on contralateral disease, even in women with ER-negative disease.
Relevant
Articles:
Selective
estrogen receptor modulators: Structure, function, and clinical
use [Review]. Osborne,
C. K. and Fuqua, S. A. W. Journal of Clinical Oncology. 18(17):3172-3186,
2000 Sep.
Similarities
and distinctions in the mode of action of different classes of antioestrogens
[Review]. Wakeling,
A. E. Endocrine-Related Cancer. 7(1):17-28, 2000 Mar. No abstract
Approaches
targeted to estrogen receptors for treatment of tamoxifen-resistant
breast cancer: A brief overview. Terakawa, N. (Reprint available from: Terakawa N Tottori Univ,
Sch Med, Dept Obstet & Gynecol Yonago Tottori 683 Japan)..
Oncology. 59(Suppl 1):3-4, 2000. No abstract
Preliminary
assessment of cognitive function in breast cancer patients treated
with tamoxifen. Paganini-Hill,
A. and Clark, L. J. Breast Cancer Res.earch & Treatment. 64(2):165-176,
2000 Nov.
Symposium
overview: Estrogens and antiestrogens in managing the patient with
breast cancer. Newman,
L. A.; Wood, W. C.; Sellin, R. V.; Morrow, M.; Vogel, C., and Singletary,
S. E. (Reprint available from: Singletary SE Univ Texas, MD Anderson
Canc Ctr, Dept Surg Oncol 1515 Holcombe Blvd,Box 106 Houston, TX
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In process
The
ovary: cysts, screening, and tamoxifen. Mourits,
M. J. E.; van der Zee, A. G. J.; Willemse, P. H. B., and de Vries,
E. G. E. (Reprint available from: de Vries EGE Univ Groningen Hosp,
Dept Med Oncol POB 30 001 NL-9700 RB Groningen Netherlands). Lancet.
355(9220):2078-2079, 2000 Jun 10.
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(Reprint available from: MacCallum J Napier Univ, Dept Life Sci
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British Journal of Cancer. 82(10):1629-1635, 2000 May.
How
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Pavil 8258 Chicago, IL 60611 USA). Journal of the National Cancer
Institute. 92(2):92-94, 2000 Jan 19. No abstract
Serum
lipid levels during and after adjuvant toremifene or tamoxifen therapy
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available from: Joensuu H Univ Helsinki, Cent Hosp, Dept Oncol Haartmaninkatu
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One
step forward or one step back with tamoxifen? Gelmon, K. (Reprint available from: Gelmon K British Columbia
Canc Agcy Vancouver BC V5Z 4E6 Canada). Lancet. 356(9233):868-869,
2000 Sep 9. No abstract
Endometrial
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R.; Khanna, S.; Al-Azzawi, F.; Bell, S. C., and Taylor, D. J.. Lancet.
356(9243):1711-1717, 2000 Nov 18. No abstract
Combined
endocrine therapy for breast cancer - New life for an old idea? Davidson, N. E. (Reprint available from: Davidson NE Johns Hopkins
Oncol Ctr 1650 Orleans St, Rm 409 Baltimore, MD 21231 USA). Journal
of the National Cancer Institute. 92(11):859-860, 2000 Jun 7. No
abstract
Risk
and prognosis of endometrial cancer after tamoxifen for breast cancer. Bergman, L.; Beelen, M. L. R.; Gallee, M. P. W.; Hollema, H.;
Benraadt, J., and van LeeuwenF. E.. Lancet. 356(9233):881-887, 2000
Sep 9. IN PROCESS
Youth
and hormone receptors in breast cancer: good or bad news first?
Stockler, M. and Beith, J. (Reprint available from: Stockler
M Univ Sydney, Natl Hlth & Med Res Council, Clin Trials Ctr,
Dept Med Sydney NSW 2006 Australia). Lancet. 355(9218):1839-1840,
2000 May 27. No abstract
